Applicant is the inventor of U.S. Pat. No. 5,974,749 issued Nov. 2, 1999 which is hereby incorporated by reference. In this patent, there is disclosed a dust and debris disposal system adapted to be mounted over an opening formed in a floor. A housing is anchored to a flat upper surface of the floor around the opening and includes a raised support shell having a plurality of dust loosening ribs extending forwardly and perpendicularly and fixed from a rear portion of the shell. With this construction, dust and debris gathered from the floor with the use of a broom or mop is swept to the front of the housing, and deposited into a dust and debris orifice formed between the front of the housing and the forward tips of the dust loosening ribs. Dust and debris entering the orifice will fall by gravity, typically to a receptacle, beneath the floor. Dust and debris attached to the broom or mop is dislodged therefrom for release into the orifice by engaging the broom or mop against the dust loosening ribs.
Applicant has discovered that the fixed nature of the dust loosening ribs creates some limitations in or drawbacks to the dust and debris disposal system. For example, it is desirable to make the dust loosening ribs movably mounted relative to the housing so as to allow for better maintenance and cleaning of the dust and debris disposal system. Further, it is desirable to make the dust loosening ribs movable so that in the event a person, particularly a child, lodges his/her fingers/hand in the orifice between the tips of the dust loosening ribs and the floor or front of the housing, the ribs will move upwardly to free the jammed fingers/hand without injury thereto.